Double-exposure preventer for cameras



w. H. IOUCHEIIE. DOUBLE EXPOSURE PREVENTER FOR CAMERAS.

APPLICATION FILED APR, Is. 1919. 1,326,119. Patented-Dec. 23,1919.-

j UNITED sTATEs PATENT oEEIoE.

WILLIAM HOWARD TOUOHETTE, OE BURLINGTON, VERMONT, AssIeNoR OE ONE-HALE To EOsTER R. CLEMENT, OE BURLINGTON, VERMONT.

, DOUBLE-EXPOSURE PREVNTER FOR CAMERAS.

Speeieation of Letters latent.

. Patented Dee. 23, 1919.

Application led April 18, 1919. Serial No. 290,957.

l vented a new and Improved Double-Exposure Preventer for Cameras, of which the vfollowing is a full, clear, and exact description.

The present invention relates to new and useful improvements in cameras, and pertains more particularly to an attachment to the shutter-actuatin mechanism thereof.

It is the primary Object of the present invention to providemeans wherebyl accidental double exposure of a film or plate is l prevented.

It is a further Object of the present invention to provide means for preventing successive operations of the shutter-actuat- Ing mechanism until the film spool has been operated to properly position an unexposed lm, or until the manually operated device herein referred to is released.

. It is a further object of the resent invention to provide means by W 'ch a second operation f of the shutteractuating mechanism is prevented when 4taking socalled snap shots, and, at the same time, provide means for releasing the shutter mechanismto permit of the taking of time exposures.

With the above and other objects in view, reference is had to the accompanying drawings in which Fi re 1 is a front elevation of'a camera showing -the .present invention attached thereto l. Fig.` 2 i's a longitudinal sectional view showing one of the steps in the operationof the device;

' Fio. 3 vis a similar view showing another step 1n the operation of the device;

nates the exible connection between the shutter-operating'- mechanism and the housing 13. This I"connection -12 between the which latter is connected to the arm 39 of VshutterL-pperating'mechanism andthe hous-I woven fabric tube 14, through which is passed a flexible wire 15, and said wire is surrounded by a spring as in the ordinary manner.

. Mounted in one end of the housing 13, is

v the stem 16, 1s a plunger 18, and said plunger is provided at its forward end with .projecting ears 19. Pivotally secured in -a steml, and carried o'n the outer end the projecting ears 19, as at 20, is a pawl 21, and saidpawl is'provided with a lurality of spaced fingers 22, 23 and 24. ne wallof the housing 13 is cut out to piovi'de a recess 25, which terminates in awall 26,

and rigidly secured, as at 27, to the outer wall of the housing, is a resilient lever 28,

and said lever has a right-angular end 29, which projects through anopening 30, into therecess 25. Y

Rigidly secured in one end of the housing 13, 1s a tubular member 31, andsaid` tubular member 31has one of its ends proj ecting beyond the end of the housing.` The woven fabric 14 has its end connected to the projecting end of the tubular member 13, and the flexible wire'15, which passes through said woven fabric tube 14, passes through the tubular member 31, as at 32, and has its free end lying within the housing 13. The free extremity of the extension 32 of the flexible wire 15, is provided with an enlarged head 33, and said head 33 is @fabric tube 14, s1milar to the one heretofore mentioned. Passing through the tubular member 34 and the woven fabric tube 14, is a flexible wire 35 moving freely in 'the tubular member 34, one end of which wire is projected beyond the end vof the tubular member 34, as at 36, and is adapted for engagement .with the finger 24 of the pawl 21.

'The opposite end of the flexiblewire member 35 is led into'the camera box, as at 37, and is engaged within a coil spring 38,

a pawl 40. This pawl 40 has an arm 41, which carries a suitable signaling device 42, and said pawl40 is mounted: for movement about the axis 43 of the winding spool of the Hlm mechanism by a frictional engagement.

The specific construction of the last mentioned portion of the device forms no part of the present invention, but is the subject matter of a separate application, Serial No. 252,892, filed by me September 6, 1918.

.Having thus described the inventlon, the operationvthereof is as follows: Assunnng that an unexposed film has been positioned within the camera, and the several parts of the device are in the position shown in F 1g. 2, to make an exposure on the ilm,the operating button 17 is depressed and the plunger 18 is moved longitudinally ofthe housing 13. This movement of the plunger 18 causes a movement of thevlexible wire 15, through the medium of its extension 32 engaging the pivoted pawl 21. Simultaneously with this operation, the finger 24 of the pawl 21 engages the extension 36 of the flexible wire 35, vas shown in Fig. 2. With the parts in this position, if the operating button 17 be Afurther depressed, it will be apparent that owing to the engagement of the extension 36 of the flexible wire 35 with the nger 24 of the pawl 21,*the finger 22 of said' pawl will be rocked out of the recess 25 and will be free to pass the projecting wall 26. Upon further depression of' the operating button 17,v

the shutter-actuating mechanism Ais operated to make the exposure, and through the medium of the iexible Wire 35, the signal 42 is moved in front of the sight opening 44. The positions of the several parts with the button 17 depressed, are shown in Fig. 3, and when pressure is relieved from the button 17, the resilient construction of the flexible wire 15 serves to.v return the same to the position shown in Fig. 2, While the extension 36 of the vwire 35 remains in the position shown in Fig: 3, due to the fact that said wire 35 is-not provided with resilient means for returning the same to the position shown in 1fig-2gl "If, now, it will be seen that the Enger 22 of the pawl 21 will engage the wall 26 of therecess 25 and prevent movement of the plunger. 18 longitudinally of the housing 13, to again opcrate the shutter mechanlsm and, therefore,

the possibility of makitleig a double exposure.

onl the lm is elimina If the film roll be turned to position an' unexposed filmy behind vthe shutter,l thearm 39 of the pawl'40 forces the iexible wire 35- back to the position shown in Fig. 2 where its other end engages the If the button 17" be depressed, it will be seen that the above-described operation will be repeated'- i In the taking of time exposures, it is necesthe button 17 be again depressed,

finger 23 of Athe y in.F ig. 3, with the shutter open, the removal of pressure on the button v17, permits the parts to return to the position shownfin Fig. 2, with the extension 36 of the wire 35 occupying the position shown in Fig. 3. With the parts in this position, it will be seen that if the operating button 17 is depressed, the finger 22 of the pawl 21 will engage the wall 26 of the recess 25, and prevent movement of the plunger 18 longitudinally of the housing 13 to operate the shutter to close the' same. If, now., however, the resilient lever 28 be depressed, as shown in full-lines in Fig. 3, it will be seen that the finger 22 of the pawl 21 will be rocked out of'engagement with the wall 26 of the recess 25, andthe plunger 18 will then be free to move longitudinally of the housing 13 to permit of closing the shutter.

From the foregoing, it will be apparent that the present invention not only provides means whereby the double exposure of a film is prevented, but, at the same time,

permits of a double operation ofl the shutter mechanism for the purpose of taking time exposures.

Having thus described the invention, what is claimed as new is- 1. A device of the character described comprising a housing provided in one ofits walls with a shoulder, a shutter-releasing mechanism carried by sai-d'housing, means darried by said shutter-releasing mechanism for engagement with the shoulder of housing to prevent movement of the shutter-releasing mechanism, and manually operated means for releasing said shutter-releasing mechanism.

2. In combination with a camera, its shutter-actuating mechanism, and its film mechanism, a housing provided onits interior with a projectingwall, a plunger movable longitudinally of said housing to operate the shutter actuating'mechanism, a 'pawl pivotally carried by said .plunger and adapted to engage the projecting wall in said housing to prevent movement of the plunger longitudinally thereof,- means operated byl the Afilm mechanism for djsengaging said pawl from the projecting wall, and means independent of the means operated by the from the wall ofthe housing. 3. In oo mbinationwith a camera, its shutter-actuating mechanism, and its film-windilm mechanism for disengagingA said pawl ing'mechaniSm, a housing provided on its 1nter1or wlth a projecting wall, a plunger movable longitudinally of said housing to operate a paWl carried by the plunger and adapted for engagement with the projecting Wall of the housing to prevent movement 5 of the plunger therein, means movable longitudinally of the housing and operated by the film Winding mechanism for disengaging said paWl from said projecting Wall', and separate means for disengaging said pawl from said projecting Wall, said separate 10 means comprising a resilient lever carried by said housing.

WILLIAM HOWARD TOUCHETTE. 

